World leaders, government representatives and aid groups are meeting in Istanbul for a UN-backed humanitarian summit. The meeting seeks to transform the world's response to crises triggered by conflict and climate change. UN officials said the summit aims to find a new approach to crises by tackling the root causes of conflict rather than just their aftermath.

The summit will call for respect of international humanitarian law which has been badly frayed by attacks on schools and hospitals in the conflicts in Syria, Afghanistan and Yemen. With some 60 million people displaced around the world and at least 125 million requiring assistance and protection, organizers say the need for action is more urgent than ever.